Electrolysis

[Head Womble]

Definitely going to use this method again, really pleased with the way the blades turned out (assuming they don't shatter).

This is what they looked like after painting and sharpening ...

Now you need to test it, I hear Chug needs his field mowed............

[Julian]

I've tested it already ... it goes round.

[Jamesrl]

I've tested it already ... it goes round.

Ain't gonna cut much grass then are you, it should be going round and round and round and round and round and round and round and round lots of times.

[Julian]

So are you saying there's a  plural of "round" ... must be an East Anglian thing along with extra digits and lusting after your cousin.

[Jamesrl]

So are you saying there's a  plural of "round"

Of course there is, the armed forces have lots of'm

[greasemonkey]

I love the look of a freshly painted and sharpened mower rotor, or blade.

For smaller stuff, I know some folks have had good success with powdered citric acid, which apparently is not over expensive.
Literally, just chuck it in the solution, and leave it for however long.

[Julian]

So are you saying there's a  plural of "round"

Of course there is, the armed forces have lots of'm

Funny you should bring that up ... i can think of a use for a couple of rounds right now.

[Julian]

I love the look of a freshly painted and sharpened mower rotor, or blade.

Great feeling of satisfaction seeing the before and after photos.

[Head Womble]

So are you saying there's a  plural of "round"

Of course there is, the armed forces have lots of'm

Funny you should bring that up ... i can think of a use for a couple of rounds right now.

The Womble runs and hides.

[Julian]

So are you saying there's a  plural of "round"

Of course there is, the armed forces have lots of'm

Funny you should bring that up ... i can think of a use for a couple of rounds right now.

The Womble runs and hides.

Don't worry, you're quite safe ... at least until the BBB.

[photoman290]

been thinking, i know bit like wanking at our age, sometimes it works most of the time it's too much effort. anyway about the brittlisation problem. it sounds lioke hydrogen brittlilisation to me. this could be caused by the H2 ions. maybe a sacrificial anode to absorb the H2 ions would work. a big chunk of zinc may work. how you test if works or not may be a problem. the zinc may even galvanise as well. i did try to find out how it all worked years ago but decided it is a bit esoteric.

[Julian]

You know how it is ... you only read the instructions after there's a problem.  Well, after my battery charger went up in smoke (broken hearted ... I've had it over 30 years) I did a bit more reading and letting the thing churn away at 6-8 amp for many hours isn't the smartest thing to do.

Many people seem to limit the current to between 2-5 amps, saying you only need more if you want to try and shift paint.  So, I've started pulling apart a PSU from a computer to make a new, dedicated power supply.  I'll incorporate the ammeter off the now defunct battery charger, but I'd like to include some means of adjusting the current.

I've read that introducing lamps into the circuit can work as can adjusting the anode area, but I believe it can also be done using a potentiometer. This is where one of my many failings comes into play ... I haven't a clue how to do it.  Can any one recommend a suitable potentiometer (the psu label say the 12v supply is 8 amps) and how to wire it up?

One further point I read was that the black deposit on the part being cleaned may, in part at least, be magnetite deposited from the anode.  Sort of makes sense as it's the same set up as for electroplating.  A suggestion to reduce this was to use carbon or graphite anodes.  I still have some carbon electrodes from a carbon arc torch that was run off an arc welder ... remember those, so when I get this new power supply working I'll give those a go.

[knighty]

computer psu will be fine running at ~8 amps 24/7

means you can get it going while you figure out a system to limit it down a bit



12v bulb in series sounds like the easiest way, but you'll need a decent bulb / headlight bulb by the time you're passing 4 amps through it

[photoman290]

you can make a variable resistor with some nichrome wire and a big croc clip. don't forget to take the plastic covering off first though or it will melt.  i used an old electric fire element and rewound it when i wanted one for a wind turbine dummy load. you need to have some idea of the range before you buy the wire. its pretty cheap and easier than bulbs.

[K.H]

I have been using Oxalic acid, 7.95 per 1kg,i read about it in this thread

http://www.volkszone.com/VZi/showthread.php?t=1360257&highlight=oxalic+acid

Is it just me? i cant see Julians pics?